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Showing posts with the label H

H bridge motor driver circuit

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Description. The circuit given here is of a simple H bridge motor driver circuit using easily available components. H Bridge is a very effective method for driving motors and it finds a lot of applications in many electronic projects especially in robotics. The circuit shown here is a typical four transistor H Bridge. The diodes D1 to D4 provide a safer path for the back emf from the motor to dissipate and thus it protects the corresponding bipolar transistors from damage. Resistors R1 to R4 limit the base current of the corresponding transistors. Working of this circuit is very easy to understand. When terminal D is grounded and A is pulled to +Vcc, transistors Q1 and Q4 will be on and current passes through the motor from left to right. When terminal B is grounded and C is pulled to +Vcc, transistors Q3 and Q2 will be on and current passes through the motor from right to right making the motor to rotate in the opposite direction. Circuit diagram. Notes. The circuit can be assembled o...

h Effect of cable capacitance

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Effect of cable capacitance Q)What is Effect of Cable Capacitance on the Operation of AC operated Contactors When long length of cables is used the stored energy in the capacitance of the cable holds the contactor even after the closing command is removed . Typical value of capacitance for two core cable is 0.3 micro farad/km Fig:Stray capacitance Remedy: 1) Use of DC control supply voltage 2) Use of lower supply voltage 3) Short circuiting of contactor coil during off command by additional bridge contacts. 4) Use of large contactors .......

DC motor driver with H Bridge IC L293D

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Making a DC motor driver with H-Bridge technique can use IC L293D as in the article "DC Motor Driver H-Bridge L293 (2 Motor DC)"is. DC motor driver L293D can be used to control the DC motor 2 pieces at once. DC Motor Driver L293D can be used to control a DC motor continuously or with a PWM technique. Dc motor driver circuit in the article "DC Motor Driver H-Bridge L293 (2 Motor DC)" only use IC L293D only. For more details see the following figure. Working system of DC motor driver L293D is to provide control signals in the form of logic or pulse to the input lines 1A - 1B for DC motor control M1 and the input 2A - 2B for the control of DC motor M2 with the following conditions: Input A Input B Motor DC 0 0 Motor silent 1 0 motor rotates counterclockwise 0 1 Motor berputer clockwise 1 1 Motor silent Description: Enable Input given a logic 1 to obtain such data in the table above.